The Cuomo Mag is a 3D printed AR-15 magazine named after the Governor of New York, Andrew Cuomo, who signed the NY SAFE Act into law banning magazines capable of holding more than 10 rounds of ammunition.[1][2] It was created by Defense Distributed and made public around January 2013 [3]
The initial prototype was created using the Objet Connex26 using VeroClear printing material (a transparent material) in order to show the magazine’s round count and feeding action[4][5] via the Fused deposition modeling (FDM) method.[6]
The magazine holds 30 rounds[3][7][2] and was able to handle enough stress to fire 227+ bullets while swapping out the barrels on the rifle to keep them cool.[2] In a test at a gun range near Austin, Texas, Defense Distributed fired a total of 342 rounds using the magazine with no issues.[2]